1. Field of the Invention
The present invention relates to a memory card connector, and more precisely, it relates to a memory card connector assembly superimposed on a substrate comprising a plurality of memory card connectors.
2. Description of Related Art
There is known a memory card connector assembly having a plurality of memory card connectors that are stacked on a substrate, so that a plurality of memory cards (e.g., IC cards) can be connected to the corresponding memory card connectors to read information recorded in the memory cards at the same time. In such a known multi-layered memory card connector consisting of, for example, upper and lower connectors, groups of contacts of the upper and lower (first and second) connectors are respectively soldered to the substrate. Upon soldering, an array of contacts from the first connector (referred to as a first contact array) is first soldered to the substrate, and thereafter, another array of contacts from the second connector (referred to as a second contact array) is soldered to the substrate.
In practice, none of the solder connections of the first contact array are visible after the soldering of the second contact array is completed. Consequently, if part of the solder connection of the first contact array is defective, re-soldering of the defective connection cannot be carried out due to interference by the second contact array. This becomes more serious when the number of layers of the connectors (memory card contact arrays) increases.
Furthermore, in a conventional multi-layered memory card connector whose contacts are all soldered to the substrate, the surface area for solder connection on the substrate is soon exhausted, thus limiting the mounting density of the substrate.